Harness mechanism for loom



' June 1956 B. w. BROUWER ET AL 2,750,966

HARNESS MECHANISM FOR LOOM Filed July 8, 1953 2 Sheets-Sheet 1 FIG.'|

lIlI'IIIII/IJ l-NVE'NTORS BENJAMIN W. BROUWE-R ALBERT PALMER ATTORNEY June 19, 1956 Filed July 8, 1953 B. w. BROUWER ET AL 2,750,966

HARNESS MECHANISM FOR LOOM 2 Sheets-Sheet 2 INVENTORS I BENJAMIN w. BROUWER 1 ALBERT PALMER ATTORNEY United States Patent HARNESS MECHANISM FOR LOOM Benjamin W. Brouwer, Auburn, and Albert Palmer, Worcester, Mass., assignors to Crompton & Knowles Loom Works, Worcester, Mass., a corporation of Massachusetts Application July 8, 1953, Serial No. 366,757

10 Claims. (Cl. 139-79) This invention relates to improvements in harness operating mechanism for looms and it is the general object of the invention to provide means by which the amount of opening of the warp sheds can be readily varied.

Certain types of harness mechanisms employ cams which operate treadle levers operatively connected to the under side of harness frames. Any given loom equipped with such mechanism may be called upon from time to time to weave fabrics having different kinds of warps and also operate with shuttles which vary to some extent in size. It is desirable to provide for adjustment of the harness operating mechanism so that the warp shed most favorable to any set of conditions may be attained. It has been proposed heretofore to provide mechanism for adjusting the amount of movement of the treadle levers, but by means so constructed as to make the adjustment possible only when the loom is at rest and at a point in the loom from which convenient observation of the Warp shed cannot be made.

It is an important object of the present invention to provide mechanism wherein the pivot of the treadle levers can be shifted during loom operation from a point in the loom from which the warp shed can be seen so that the optimum condition of shedding for any given warp'or shuttle width can be visually determined.

'It is a further object of the invention to connect the ends of each treadle lever opposite its harness connections to a link movable about a fixed axis and operating to prevent substantial endwise motion of the treadle lever as it is raised and lowered by its cam.

It is a still further object of the invention to provide a plurality of treadle levers for several harness frames and mount the shiftable center for the levers so that they can all be moved in unison from a common readily accessible point of control.

In order that the invention may be clearly understood reference is made to the accompanying drawings which illustrate by way of example the embodiments of the invention and in which:

Fig. l is a side elevation partly in section of a loom having the invention applied thereto,

Fig. 2 is an enlarged plan view looking in the direction of arrow 2, Fig. 1,

Figs. 3, 4 and are enlarged detailed vertical sections on lines 3-3, 4-4 and 5-5, respectively, Fig. 2,

Fig' 6 is a detailed horizontal section on line 6-6, Fig.5,

Fig. 7 is a detailed vertical section on lines 7-7, Fig. 1, showing a manual control mechanism for the shiftable axis of the treadle levers, and

Fig. 8 is a front elevation looking in the direction of arrow 8, Fig. l.

Referring particularly to Fig. l, the loom includes a frame 1 which supports top and bottom shafts 2 and 3, respectively, which as contemplated herein are of usual timing so that the top shaft rotates once for each pick or beat of the loom while the bottom shaft 3 operates every second pick of the loom. The loom is provided with harness frames one of which 4 is .shown in down position in Fig. 1, while another is indicated at 5 in the raised position. The loom is not necessarily limited to these two harness frames and in fact as shown in Fig. 2 six frames are set forth. Guides 6 secured to the frame of the loom, see Fig. 8, keep the harness frames spaced and guide them in their vertical motions.

The harness frames are pushed up by two sets of operating mechanisms A and B located at the left and right, respectively, of Fig. 8. These mechanisms are essentially the same except that they are of opposite hand and a detailed description will be given of mechanism A only.

The loom includes in its construction a back girt 10 to which are secured two forwardly extending supports 11 and 12 the forward ends of which support a cam shaft 13. This cam shaft has secured thereto a sprocket 14 driven by a chain 15 meshing with a sprocket 16 secured to bottom shaft 3. Sprocket 14 is twice the diameter of sprocket 16 so that shaft 13 rotates once for each four icks or beats of the loom. This particular timing of shaft 13 is not essential and is set forth herein for illustrative purposes only. Secured to shaft 13 are harness operating cams 17 which are distributed angularly around the shaft 13 in known manner. In the present instance mechanism A has six cams and six harness or treadle levers 20 positioned for actuation by their cams. The forward or left end of each lever 2t), Fig. 1, is operatively connected to the lower end of a rigid connector 21 extending upwardly to be connected as at 22 to the lower part of the associated harness frame. Each harness frame is pulled down by springs 23 so that a roll 24 on each treadle lever is held down on the top of its cam.

Much of the mechanism thus far described may be similar to known mechanisms in cam harness motion looms except that in the present instance the treadle levers 20 are above their cams so that the harness frames can be lifted against the action of their springs through the rigid connectors 21.

The invention relates to means for shifting the axis of the treadle levers and in carrying the invention into effect each lever is provided with a slot extending generally lengthwise thereof and formed by a top surface 31 and an end surface 32 cut or otherwise provided on the lever, and also by a bottom surface 33 and an end surface 34 at the opposite end of the slot provided by a cap 35. The latter is held to the lever by screws 36 and 37 and has an car 38 which is pivoted at 39 to a link 40 rockable about a stationary pin or rod 41 mounted in a stand 42 fastened to the rear girt 10. The link prevents substantial endwise movement of the treadle levers.

The slots 30 of the several levers are aligned so .that pivot means, such as a rod 45, can extend through them. Rod 45 passes through a block 46 provided for each treadle lever and slidable in the associated slot 30. The ends of the rod 45 are mounted on the upper parts of the supports 11 and 12 each of which has a horizontal slot 50. As shown in Fig. 4 the slot of support 11 is formed partly by the support and partly by a cap 51 similar to cap 35 and held in position by screws 52 and 53. It is to be understood that each of the supports 11 and 12 for the mechanism A will be made as shown for instance in Fig. 4 so that the ends of the rod 45 are guided to move horizontally by reason of the slots 50. Blocks 54 similar to blocks 46 are provided for the ends of rod 45 and are slidable in the slots 50.

Each end of rod 45 extends beyond its cap 51 and fits into an open bearing in the upper end of a positioning or control lever 61 keyed as indicated in Fig. 3 to a rock shaft 62 journaled for rocking movement in the supports 11 and 12. The levers 61 and shaft 62 rock in unison and the slots 63 in the upper end of the levers 61 accommodate the arcuate movement of the levers 61 to the straight line motion of rod 45 along slots 50.

A control rod 65 is pivotally connected at its rear end as at 66 to one of the control levers 61 and its forward end is pivoted at 67 to a manually operated control mechanism 'M. The latter, shown in Figs. 1 and 8, includes a lever 68 secured by set screw 69 to a shaft 70 which extends across the front of the loom to mechanism B and is journaled in the loom frame.

The loom frame has secured thereto a plate 72 having notches 73 radiating from the axis of shaft 74 and adapted to receive the lower end of a lock means or detent 74 pivoted to lever 68 as at 75. The detent has a hand hold 76 extending upwardly from the pivot 75 and held normally spaced from the lever 68 by a compression spring 77. The latter spring normally holds the detent in one or another of the notches 73 of the plate 72 so that under normal conditions the angular position of the lever 68 is fixed.

In the operation of the mechanism thus far described it may be assumed that the lever 68 is in its forward position as shown in Fig. 1, thereby causing the positioning levers 61 to locate rod 45 and blocks 46 in the left hand forward part of the slots 30 as shown in Fig. 5, relatively near the cams and shaft 13. When rod 45 is thus placed it will cause a relatively large motion of the forward or left ends of the levers 20, Fig. l, as shaft 13 rotates to produce a relatively large warp shed.

If it should be desired to reduce the warp shed during operation of the loom the hand hold 76 will be moved toward the lever 68 to release the lock means by detaching the detent 74 from the notched plate 72, after which the lever 68 will be moved rearwardly or to the right as viewed in Fig. 1, so that the rod 65 serving as operative connections between lever 68 and one of the control levers, will have the effect of swinging the control levers 61 in a clockwise direction as viewed in Fig. 3 and thereby move the rod 45 and the blocks on it toward the right hand end of the slots 30 away from the cams and thus reduce the amount of vertical motion of the forward ends of the treadle levers 20. This operation can be performed during a period of loom operation so that the extent of opening of the warp shed can be changed for successive picks of the loom. After the correct position of lever 68 is found which produces the optimum shed the hand hold 76 will be released and the detent 74 will enter one of the notches 73 to lock the lever 68 and also the levers 61 and rod 45 in their newly adjusted position.

During the rising and falling of the treadle levers 20 due to action of their cams they will turn primarily around rod 45 as the principal axis whatever the position of the rod 45 may be along the slots 30. During angular motion of each treadle lever its link 40 will rock slightly around the rod 41 and hold the rear end, or the right end as shown in Fig. 5, of the treadle lever against substantial endwise motion. Thus, when a treadle lever is down as indicated in Fig. 1 its link 40 will be in a slightly upwardly inclined position, but when the lever is raised by its cam and turns around the rod 45, the link will then swing to a slightly downwardly inclined position.

The blocks 46 have a slight turning motion on the rod 45 and sliding in slots 30 during rocking of the treadle levers by their cams. There is, however, no corresponding rocking of the blocks 54 with respect to the ends of the rod 45 during movement of the treadle levers 20. The slots 50 cause the rod 45 to move in a substantially horizontal plane when the lever 68 is adjusted and they determine the position of the blocks 46 which are slidable in the slots 30. Mechanism A has been described in detail, but mechanism B is similar to it except that its adjustment will be effected through an arm 80 secured to the right end of rod 70, Fig. 8, and serving the same purpose as the lower part of lever 68. By this arrangement only one manual control means is required.

From the foregoing it will be seen that the invention sets forth a harness mechanism wherein the pivot of the treadle levers 20 can be moved toward or away from the operating cams by the lever 68 during loom operation for the purpose of determining the most favorable shed opening for any given shuttle or warp condition. It will further be seen that the links 40 provide a simple means for preventing objectionable endwise motion of the treadle levers while permitting them to be rocked around their pivot rod 45. Also, the rod 45 extends through the slots 30 of the treadle levers but is guided in its back and forth motion by stationary slots 50. The blocks 46 are slidable on the long sides of the slot 30 when an adjustment is made by means of lever 68 and also have slight sliding motion in their slots 30 due to the small endwise motion of the treadles resulting from a rocking of the links 40. Furthermore, the control mechanism is so located that a person manipulating it can readily observe the warp shed.

Having now particularly described and ascertained the nature of the invention and in what manner the same is to be performed, what is claimed is:

1. In a loom having a plurality of harness frames and a cam shaft having secured thereto a plurality of cams, a treadle lever for each harness frame operatively associated with the corresponding cam, each treadle lever having one end thereof operatively connected to its harness frame and having the opposite end thereof provided with a slot extending lengthwise of the lever in a direction generally toward and from the cam shaft, pivot means common to the treadle levers extending through the slots thereof mounted for movement in a direction along said slots, manual control mechanism, and operative connections between said mechanism and said pivot by which the position of the latter along the slots can be changed by manipulation of said manual control mechanism.

2. The structure set forth in claim 1 wherein the pivot means comprises a rod extending through said slots and having the ends thereof operatively connected to control levers pivoted with respect to the loom for movements in unison in directions toward and from said shaft and said operative connections are connected to one of said control levers.

3. The structure set forth in claim 1 wherein the loom is provided with a second shaft parallel to the cam shaft and having control levers secured thereto operatively related to said pivot means, and said operative connections are connected to at least one of said control levers to rock said second shaft and operate both of the control levers simultaneously to effect movement of the pivot means along said slots.

4. The structure set forth in claim 1 wherein the manual control mechanism includes detachable lock means normally operative through said control mechanism and operative connections to hold the pivot means stationary but releasable to enable the manual control mechanism acting through said connections to effect said movement of the pivot means toward and from said axis.

5. The structure set forth in claim 1 wherein the manual control mechanism includes a lever pivoted at the front part of the loom in such position as to enable a person manipulating the manual control mechanism to see the warp shed produced by the harness frames.

6. The structure set forth in claim 1 wherein the manual control mechanism is normally locked to hold the pivot means in fixed position.

7. The structure set forth in claim 1 wherein the manual control mechanism includes lock means normally in locked position to hold the pivot stationary but releasable to permit movement of the manual control mechanism to effect movement of the pivot.

8. The structure set forth in claim 1 wherein there is provided means for preventing substantial endwise motion of the lever comprising a link having one end thereof pivoted to the lever and having the other end thereof pivoted about a fixed axis.

9. The structure set forth in claim 1 wherein the slot is formed in part by the lever and in part by a removable cap secured to the lever, the slot extending lengthwise of the lever.

10. The structure set forth in claim 9 wherein a link having one end thereof pivoted to the cap and having the other end thereof pivoted about a fixed axis prevents substantial endwise movement of the lever.

References Cited in the file of this patent UNITED STATES PATENTS 

